display MAZDA 323 1992 Workshop Manual Suplement

F3 SELF-DIAGNOSIS FUNCTfON
SELF-DIAGNOSIS FUNCTION
OUTLINE
Theself-diagnostic function and diagnosis procedure are the Same as for the previous 4WD model. How-
ever, there is an additional service (malfunction) code (N0.35) for the new modet.
13EOF3-321
SERVICE CODE NUM8ERS
Sensor or
subsystem
NE-signal
G stgnal
Knock sensor I Malfunction display
Cond &ion Fail-safe
Service
code no. Output signal pattern
No NE-signal
ON
-
02
OFF
M
No G srgnal Cancels two-group injection ON
03
OFF
ml
Open or short circuit
pressure sensor
F3-16
--
I

F3 TROUBLESHOOTING GUIDE
SYMPTOM TROUSLESHOOTING
2 . CRANKS NORMALLY BUT WILL NOT START (NO COMBUSTION)
LIESCRIP-
l Engine cranks at normal speed but shows no sign of firing l Battery in normal condition
TION *Throttle valve not held fufly open while cranking (dechoke system not operating}
l Fuel in tank
UROOBLESHUOTlNG HINTS]
@ No spark
@.I low fuei tine pressure
l Ignition control malfunction @I Low engine compresslon l Ignition system component malfunction
@ No fuel injection
l Fuel pump inoperative l Ihjectors inoperative
;TEP
INSPECTION
I ACTION
1
Is strong btue spark visible at disconnected high- Yes Go to Step 3
tension lead?
NO Go to Step 2
2 Is “00” dlsplayed on Self-Dlagnosjs Checker
Yes
with ignltron switch ON? Check rgnltion system (Refer to
Troubleshooting “Misfire”)
c7 Section G
SYSTEM SELECT: 1 No
Service Code No. displayed Check for cause (Refer to specified
check sequence)
G- page
F3-16
“66” flashes
Check ECU termrnal 1F voltage
3 page W-45

Voltage: Battery vabage
(ignition switch ON)
W: SELF TEST C+ If OK, replace ECU
4 If not OK, check wiring
CT page F3-2
(ECU
- Self-Diagnosis Checker)
3
Connect diagnosis connector terminals F/P and
Yes
GND with jumper wire; IS fuel pump operating Does engine start in this condition?
sound heard wjth ignition switch ON?
4 If it does, check circuit-opening
relay
4 If it does not, go to Step 5
No Go to next step
F3-22
iTEF
6
8

F3 TROUBLESHOOTING GUIDE
I- STEP lNSPECTlON ACTION
Yes Go to Step 8
5 In same condition as in Step 2, IS fuel ilne pres-
sfire held after Igrxtbon swatch rs turned OFF?
Fuel line pressure: More than 147 kPa
Il.5 kgflcm’, 21 Psi 1 for 5 min.
6 In same condition as in Step 3, IS fuel line pres-
sure held after lgnltron switch IS turned OFF?
Fuel line pressure: More than 147 kPa
{ t.5 kgf/cm*, 21 psi) for 5 min.
No
I Go to next step
Plug both vcuum ports of pressure regulator; IS
fuel lme pressure held after ignltlon switch is
turned OFF? Yes Replace pressure regulator
r~ page F3-3
Fuel line pressure: More than 147 kPa
{ 1.5 kgf/crn*, 21 psi] for 5 min.
NO Check fuel pump hold pressure
e If OK, check InJector for fuel
leakage
e If not OK reptace fuel pump ZF- page F3-42
T page F3-3
8 Dlscofinect water thermosensor connector, does
engtne start? Yes Check water thermosensor
e ff OK. check connectrons of water
thermosensor and ECU 2Q terminal
Q If not OK, replace water thermo-
sensor
ET page F3-13
No 1 Go to next step --~
Is “00” drsplayea on Self-Diagnosis Checker
with ignition switch ON? 9 Yes Go to next step
NO Service Code No. displayed
Check for cause (Refer to specified
check sequence)
c7 page F3-16 SYSTEM SELECT, 1
“88” flashes
Check ECU terminal IF voltage
KIT page F3-45
Voltage: Battery voltage
(ignition switch ON)
e If OK, replace ECU
ET- page F3-2
e If not OK, check wiring
(ECU - Self-Diagnosis Checker)
Y %EtECT SW: A
Yes 1 Go to next step 10 Are rf ECU termrnaf voltages are OK?
(especjaffy 1C. 2D. and 2Q)
CT page F3-45
NO Check for cause
Yes Replace ECU
=T page F3-2
No Change to another brand of fuel
13EOF3 331 Try known good ECU, does condition improve?
CT page F3-2
F3-26

TROUBLESHOOTING GUlDE F3
7 CRANKS NORMALLY BUT HARD TO START - AFTER WARM-UP
*
l Engrne cranks at normal speed but requkres excessive cranking time before starting after running and being
DESCRIP- hot soaked
TION
l Battery rn normal condition l Engine starts normatly when cold
*Engine runs normally at Idle (If idle condrtron is not OK, refer to “Rough idle” ~Nos. 8-l 21)
[ ~ROUBLESHOOTLNG HINTS1
[ i 5 ArrlFuel mixture too Rich - l Fuel rqection control malfunction l lnpector fuet leakage
I
TEP tNSPECTlON @ Vaporlock
l Fuel pressure not held rn fuel line after engrne IS
stopped
l Pressure regulator control system malfunction
I ACTION
1 Is “00” dispiayed on Self-Diagnoses
Checker wrth rgnrtron switch ON7
SYSTEM?_SELECT. 1
SELECT SW. A
Remove vacuum hose from pressure regulator
(port A) ancI plug rt. dOt?S engine start normally’-,
Remove both vacuum hoses from pressure regu-
lator (ports A and Bj and plug them; does en-
gine start normally7
@
PtUG
/ /
Are ECU terminal voltages OK
(especially 1 C, 20, 20 and 2T)?
w page F3-46 Yes Go to next step
No Service Code No. displayed
Check for cause (Refer to specified
check sequence) CT oaae F3-16
“88” flashes
Check ECU terminal 1F voltage
Voltage: Battery voltage
(ignition switch ON) w page F3-45
( cs> It OK. replace ECU
/ w page F3-2’
3 If not OK, check wlrtng
(ECU - Self-Dlagnosrs ChecKer)
Yes Check pressure regulator control sys-
.
tern (high temperature operation) w page F3-43
I NO Go to next step
Check pressure regulator control sys-
tem (low temperature operation)
No 1 Go to next step
Yes Go to next step
NO Check for cause
F3-27

TROUBLESHOOTING GUIDE F3
8
1 ROUGH IDLE/ENGINE STALLS AT IDLE - ALWAYS
DESCRtP- 1 l Engine starts normally but stalls or vibrates excessively at idle in every condition
TION
[TROUBLESHOOTiNG HlNTSJ @ Air/Fuel mixture tw lean @ Incorrect idle-speed l ldiespeed misadjustment l Idle-speed control malfunction
$I One or more spark plugs not firing
9 Low engine compression
B Airflow meter stuck l Air leakage l Fuel injection control malfunction
*Low fuel line pressure
@ One or more injectors clogged or not
@ Low intake air amount operating
INSPECTION
Is “00” displayed on Self-Diagnosis
Checker with ignition switch ON?
1
SYSTEM SELECT: 1
ACTION
Go to next step
Service Code No. displayed Check for cause (Refer to specified
check sequence) c7 page F3-16
“88” flashes
Check ECU terminal IF voltage
(17 page F345
--.
‘\.
Voltage: Battery v&age
(Ignition switch ON)
4 If UK, replace ECU IT page F3-2 c3 If not OK, check wiring
(ECU - Self-Diagnosis Checker) Y -SELECT SW: A
Are ECU terminal voltages OK
(especially 20, 20, and ZQ)?
D page F3-45 Yes
Gu to next step
NO Check for cause
Disconnect each high-tens&on lead at idle: does
engine speed decrease equally at each cylindeR Yes Go to Step 9
NO Go to next step
Is injector operating sound heard at idle? [ Yes Go to Step 7
t- NO Stop engine and go to next step
Yes Check if injector resistance is OK
CT page F3-41 Is there battery voltage at each injector connec-
tor (No.1 (P), No.2 (R), No.3 QV), No.4 (0)) with
ignition switch ON?
Resktance: Approx. 2.110
(at 20*C [68*F))
4 if it is, check wiring
(ECU - Injector)
c3 If it is not, replace itijector
Go to next step
NO
Is there battery v&age at injector resistor (W/R)
I .Yes
with ignition switch ON? Check mjeotor resistor
4 tf OK, check for short circuit in wir-
ing (Injector resistor-Injector)
e3 If not OK,’ replace injector resistor
Check for open circuit in wiring (Main
relay (FUEL INJ relay)-Injector resistor)
Go to next step
t NO 1
Is strong blue soark visible at each disconnected Yes
‘Check ‘high-tension lead
4 If UK. check distributor cap and
rotor .
c3 If not OK, replace high-tension lead
‘-F3-29

TROUSLESHOOTING GUIDE F3
10 ROUGH IDLE/ENGINE STALLS AT IDLE - AmER WARM-UP
DESCRIP- -Engine runs normalty at idle during warm-up but engine stalls or vibrates excessively after warm
TlO#
TROUBLESHOOTING HINTS]
3 Idle-speed control system malfunction
3 Air/Fuel mixture too lean
l Air leakage
*Low fuel line pressure
TEP
INSPECTION
1
ts “00” dlsplayed on Se\-Diagnosis Checker
with ignition switch ON?
SYSTEM SELECT: 1 @ Air/Fuel mixture too rich
l Fuel injection control malfunctlon
(correction for coolant tem$eratuie)
@ Poor ignition
@ Low engine compresslon
ACTION
YES Go to next step
No Service
Code No. displayed
Check for cause (Refer to specified
check sequence)
w page F3-16
“88” flashes Check ECU terminal IF voltage w page F345
Voltage: Battery voltage
(ignition switch ON)
W: SELF TEST e !f UK, replace ECU
w page F3-3 c3 ff not OK, check wiring
(ECU - Self-Diagnosis Checker)
2 Are ECU termrnal voltages OK Yes Go to next step
(especially 20, 20, and 2Q)?
w page F3-45 No
Check for cause
3 Disconnect each high-tension lead at idle; does Yes Go to next step
engine speed decrease equally at each cylinder?
NO Go to Step 9
4 Is intake manifold vacuum correct at idle? Yes Go to next step
Vacuum: More than 450 mmHg f 17.7 InHg )
NO Check for air leakage of intake air sys-
tem components
5 Is air cleaner element clean? Yes Go to next step
No Replace air cleaner element
F3-3 1

TROUBLESHOOTING GUlbE F3 1
14 IDLE MOVES UP AND DOWN/IDLE HUNTS
IESCRLP-
l Engine speeds up and down periodically at idle
UON
TROUBLESHOOTING HINTS]
B Idle switch (En throttle sensor) OFF at idle
3 Air leakage
3 Fuel injection amount Inconstant
. Poor contact point inside airflow meter
9 Poor ignitron
rEP[ INSPECTION
I is “00” displayed on Self-Dragnosis Checker
with ignrtron swatch ON?
SYSTEM SELECT: i I ACTfON
Yes Go to next step
NO Service Code No. displayed
Check for cause (Refer to specified
check sequence) c=;r page F3-16
“86” flashes

Check ECU terminal IF vottage csr page F345
Voltage: Battery voltage
W: SELF TEST (ignition switch ON)
SELECT SW: A
.d P/ e If OK, replace ECU CT page F3-3
c3 If not OK, check wrrjng
(ECU - Self-Dlagnosls Checker)
2 Is intake manrfold vacuum correct at idle? Yes Go to next step
Intake manifold vacuum:
More than 450 mmHg { 17.7 inHg )
No Low vacuum
Check for air leakage at intake air
system
3 Is air cleaner element clean? Yes Go to next step
No Replace abr cleaner element
4 Disconnect each hrgh-tension lead at idie; does Yes Go to next step
engine speed decrease equally at each cylinder?
No Go to Step 8
5 Are ECU terminal voltages OK? Yes Go to next step
(especially 20, 2Q, 20) -
rI7 page F345 No
Check for cause
6 Connect System Selector to diagnosis connector Yes Go to next step
and set Test Switch to SELF TEST; is ignition
timing at idle correct after warm-up?
Ignition timing (BTDC): f 0 f la
No Adjust ignition timing
._
. F3-33

TROUBLESHOOTING GUiDE F3
15 ENGINE STALLS ON DECELERATION
IESCRIP-
l Engrne unexpectedly stops running dunng or after deceleration
[iON l Idle condition normal.
TROUBLESHOOT1NG HtNTS]
ingrne speed drops too much when releasrng accelerator
3 Idle-speed misadjustment @I Loose connector disconnected by force of deceleration
3 Fuel-cut contrd malfunction
TEP lNSPECTlON ACTION
1 1s idle condition normal? Yes Go to next step
tdle speed: 800 f 50 rpm (in neutral)
NO Adjust or perform Troubleshooting, Nos.
8-I 1 “ROUGH IDLE”
(Refer to Workshop Manual
(1203-I o-89F))
2 Is “00” displayed on Self-Diagnosis Checker Yes Go to next step
with ignition switch ON?
SYSTEM SELECT: 1 NO Service Code No. displayed
Check for cause (Refer to specified
check sequence) ET page F3-16
“88” flashes
Check ECU termrnal 1 F voltage
Voltage: Battery voltage
(ignition switch ON) r;r page F346
W:SELFTEST
e If OK, replace ECU CI page F3-3
4 If not OK, check wirtng
(ECU - Self-Diagnosis Checker)
3 Does Self-Diagnosis Checker Monitor Lamp with Yes Go to next step
lgnttlon switch UN show that switches operate
correctly?
NO Lamp not ON or OFF with specified
switch
Check for cause (Refer to specified
check sequence)
W: SEtF TEST Lamp slways ON
Check wiring between
(ECU terminal 1 D - Self-Diagnosis
Checker)
4 Are ECU ?erminal voltages OK? Yes Go to next step
(especially IV, 20, 20, ZU, 2V.
and 20) v page F346 No
Check for cause
5 Check for poor connection of foltowing parts YC?S Repair or replace
l ignrtion coil l Igniter l Olstribdor l High-tension lead
NO Go to next step l Injector. l Injector resistor l Ctrcuit-opening relay . l ECU
F3-35

F3 TROUBLESHOOTING GUIDE
STEP INSPECTION ACTlON
6 Is dashpot correctly adjusted? Yes Go to next step
c
Dashpot set speed: Approx. 3,500 rpm
No Adjust dashpot
7
Try known good ECU; does condition
Improve?
w page F3-3
13EOF3-336
16 ENGINE STALLS SUDDENLY (INTERMITTENT)
DESCRIP.
l Engine intermittently stops running
TION l Before stalling, engine conditron is OK
TROUBLESHOOTING HINTS]
@ intermittently no spark or no fuel injection caused by ve-
hlcle vibratron, acceleratton, or deceleration
l Poor connectlon in wiring harness
iTEP INSPECTION ACTfON
1 Is “00” displayed on Self-Oiagnoss Checker Yes Go to next step
with lgnltlon swrtch ON?
NO Service Code No. displayed
Check for cause (Refer to speclfled
check sequence).
Note CT page F3-16
l When checking wiring harness and
connectors, tap, move, and wiggle
suspect sensor and/or harness to
recreate problem
“88” flashes ’
Check ECU terminal IF voltage
Voltage: Battery voltage
{ignition swttch ON) w page F3-45
4 If OK, replace ECU
4 If not OK, check wiring
(ECU - Self-Diagnosis Checker)
2 Check for poor connection of foliowrng parts
Yes Reparr or replace
l lgnltfon coil l Igniter l Distributor l t-flgh-tensron lead
No Go to next step l Injector l Injector reststor l Circutt-opening relay l ECU
3 Are ECU terminal voltages OK? Yes Go to Troubleshbotrng No. 2
(especially 16, 2A, 2B, and 2C) .“CRANKS NORMALLY BUT WILL NOT
w page F3-45 START (NO COMBUSTION)”
w page F3-20
Note
. No Check for cause
l When. checking voltages, tap, move, and
wiggle harness and connector to recreate
problem
* lrlrl m-7
F3-36
7.8-l

,,1
CONTROL SYSTEM F3 ‘1
Va: Battew voltage
Incorrect voltage Possible cause
Always OV
l ROOM IOA fuse burned l Open circuit In wiring from ROOM 10A fuse to ECU termina! 1A
Always OV
l Main relay malfunction l Open or short circuit in wiring from main relay to ECU terminal IB
Always OV (starter turns)
l Open or short circuit in wiring from ignition switch to ECU terminal IC
Always OV
Always VB
l Maln relay (FUEL INJ relay) malfunction l Open circuit in wiring from main relay to diagnosis connector terminal +B l Open or short circuit in wiring from diagnosis connector terminal MEN to
ECU terminal 1 D
l Poor connection at ECU connector l ECU malfunction
Always approx. 5V . ECU malfunction
Always below
2.5v
Always Ve -
-
No display on Self- * Main relay (FUEL INJ relay) malfunction
Diagnosis Checker
l Open circuit in wiring from main relay to diagnosis connector terminal + B
“88” displayed and
l Open or short clrcurt in wiring from diagnosis connector terminal FEN to
buzzer sounds con- ECU terminal tF
ti nuousl y
l Poor connection at ECU connector l ECU malfunction
Always QV
l Short circuit in wiring from igniter to ECU terminal 16
Always OV or VB
l Refer to Code No.42 Troubleshooting
(Refer to 323 4-Wheel Drtve Workshop Manual (12?9-IO-89L))
Always VB
Always OV
Always below
2.5V
Atways Ve I ’
l Fuel pump resistor/relay malfunction
l Open or short circurt in wiring from ECU terminal II to fuel pump resis-
tor/relay
A/C does not operate
l A/C reiay malfunction l Open circuit in wiring from ignition switch to A/C relay l Open circuit in wiring from A/C relay to ECU terminal 1J
A/C switch
OFF but l Short circuit in wiring from AIC relay to ECU terminal 1 J
A/C operates . ECU malfunction
l Poor connection at ECU connector l ECU malfunction
Always below 1 .OV a Short circuit in wiring from diagnosis connector terminal TEN to ECU termi-
nal 1K
Always Vs
l Open circuit In wiring from diagnosis connector terminal TEN to ECU terml-
nal IK
-
-
l Open circuit in winrig from diagnosis connector terminal GND to ground’
-
I -
.
. .
-. F3-47